Optimal treatment of exhaust air
Ventilation in a commercial kitchen
A well-designed ventilation system in a commercial kitchen is a prerequisite in achieving a good working environment. Cooking fumes, heat and odors emitted from the kitchen must be removed while fresh air needs to be supplied. The ventilation system should also ensure that the property and its surroundings don’t suffer from any unpleasant odors during operation of the kitchens.
Optimal treatment of exhaust air in three steps
Step one – Particulate filter
A well-functioning particulate filter placed inside the kitchen hood is the first important step to achieve proper treatment of exhaust air. The filter must be able to trap larger grease particles from the exhaust air before it moves on to the inlet duct. Select the particulate filter with care.
Step two – Ozone system
The exhaust air that has passed the particulate filter needs to be treated further in the next step with a treatment solution that gets rid of the large amount of small grease particles and odors that remain in the air stream.
Ozonetech offers two treatment solutions, both of which produce ozone that breaks down the smaller fat particles into carbon dioxide, water and a little dust that is then transported through the ventilation system without adhering to the inner walls of the duct. Ozone also removes the majority of all odor substances in the exhaust air.
Ozone is produced on site and injected into the exhaust air flow.
Two types of ozone systems
Air-fed ozone generator – generates ozone from oxygen in the ambient air. Mounted directly into the ventilation above the hood. Best suited for smaller kitchens with an air flow below 2,500 m3/h (i.e. 700 l/s).
High-performance ozone generator – fed with dry, pure oxygen and is mounted on the wall in a nearby area e.g. a corridor, passage or cleaning closet. Best suited for average or large kitchens, food courts etc. with an air flow above 2,500 m3/h (i.e. 700 l/s).
Step 3 – Final air treatment
In order to be able to release the exhaust air into demarcated or odor-sensitive environments, it is necessary to remove the remaining odors from the exhaust air. Read more about Nodora - our newly developed solution for treatment of all types of odor problems.
A number of parameters shall be taken into account when faced with the choice of treatment systems for commercial kitchen ventilation and exhaust ducts. Ask others that have already installed treatment systems:
What is the system’s total annual operating cost?
How often does the system require maintenance or oversight? By the kitchen staff? By authorized technicians? By duct cleaners?
Does the system require regular replenishment of some sort? Is it mandatory to stock up on chemicals? What are the by-products? Does the treatment involve frequent replacements of costly consumables?
Ozone and ozone generators have been used since the middle of the 20th century to treat both air and water worldwide. Purifying kitchen exhaust air with ozone became an established technique in the early 2000s. Using ozone and oxidation technology you can effectively break down fats, odors and other unwanted substances.
Our solutions purify the kitchen exhaust both efficiently and continuously, year after year. The systems are based on the principle of generating high-quality ozone on site that is injected directly into the exhaust airflow. However, in order to achieve an efficient ozone-based solution, there are several parameters to keep in mind, such as:
- The air flow
- Reaction time*
- Length and cross-section of the ventilation ducts
- Amount of grease
- Amount of ozone needed
- Location of ozone injection
- How the ozone is injected
- External factors that may disrupt the treatment
*To achieve decomposition of grease and odor compounds, a reaction time of at least two seconds is required. The length of the duct should, therefore, be dimensioned to ensure that at least two seconds is achieved between the injection point and the point of discharge or dilution.